| 摘要 |
To ensure oil-sealability required of an oil-sealed crawler belt and an excellent toughness against severe shock loading, to improve wear resistance and wear life, and to provide a more inexpensive manufacturing process. A crawler belt bushing has a structure wherein a hardened layer (2) on the outer circumferential surface, a quench-hardened layer (4) on the edge and a tempered martensitic layer on the inner circumferential surface are formed and a flexible layer made of at least one chosen from ferrite, pearlite, bainite, martensite and a tempered martensitic structure is formed between the outer hardened layer and the inner tempered martensitic layer. The flexible layer is connected to the inner circumferential surface at the edge part. The crawler belt bushing is manufactured through means such as preliminarily cooling the entirely heated crawler belt bushing from either the outer or inner circumferential surface and subsequently cooling the entire circumferential surface, or preliminary cooling either the inner or the outer circumferential surface while performing high-frequency heating from the other circumferential surface. |
